Pressure measurement is a well known art and there are a variety of devices which function to measure pressure and which vary in scope from devices for measuring very small changes in pressure to devices for measuring very large changes of pressure. In discussing pressure measurement, it should be borne in mind that pressure is directly related to force, since pressure is a force per unit area exerted on a surface, and thus pressure measurements are functionally related to force measurements.
An exhaustive review of various types of pressure measurement devices is not necessary for the background of the present invention because the present invention is involved with a measurement technique and measurement device which, to applicant's belief, has not heretofore been utilized i.e., a measurement of pressure based upon a relationship of the temperature and the density of a gaseous dielectric medium in a capacitor device. Conventional pressure sensors rely upon stress dependent readings. That is, some element, such as a measurement diaphragm, is stressed as a function of pressure to produce a measurement parameter. Factors such as creep and repeatability of the diaphragm affect the accuracy of these measurements. High pressure measurements typically generate high stress factors in the measuring device. The present invention involves a virtually static measurement device in which the pressure measurement is made without requiring any pressure related deflection in the capacitor device.